1. Field of the Invention
The present invention relates to machine tools.
2. Description of the Related Art
A lathe, a machine tool, includes a spindle adapted to hold and rotate a workpiece, and a tool post adapted to hold a cutting tool to cut the workpiece, and performs cutting work, while moving the workpiece and the cutting tool relatively. As such a lathe, for example, one having a loader that transfers or receives a workpiece to or from a spindle, and transports the workpiece between the spindle and a predetermined position (for example, see JP 2012-130979 A), and one that transfers or receives a workpiece to or from a spindle, using a workpiece relay device provided on a tool post (for example, see JP 2010-99747 A) are known. On the lathe described in JP 2010-99747 A, a workpiece is transferred to or received from the workpiece relay device by an operator's manual operation.
The lathe described in JP 2010-99747 A, on which an operator manually transfers or receives a workpiece to or from the workpiece relay device, thus poses a problem that, in addition to the troublesome work, it takes a longer time to transfer a workpiece between the spindle and a loader, resulting in a longer time required for entire machining. In particular, even when cutting work on a workpiece is reduced in time, the need for a longer time to transfer the workpiece makes greater efficiency of the entire machining impossible.